521 research outputs found

    Penetrating Spinal Cord Injury

    Get PDF
    Penetrating spinal cord injury (SCI) is a relatively rare entity affecting mainly young males and military personnel worldwide. These injuries are the source of permanent disabilities to the affected patient and family and have substantial social and economic concerns. This chapter is an overview of the common penetrating spinal cord injuries, their incidence worldwide, causes, primary evaluation, and treatment including medical treatment and late definitive surgical treatment. It also describes common complications and strategies preventing secondary and collateral damage and disability

    MoMo: Momentum Models for Adaptive Learning Rates

    Full text link
    Training a modern machine learning architecture on a new task requires extensive learning-rate tuning, which comes at a high computational cost. Here we develop new adaptive learning rates that can be used with any momentum method, and require less tuning to perform well. We first develop MoMo, a Momentum Model based adaptive learning rate for SGD-M (Stochastic gradient descent with momentum). MoMo uses momentum estimates of the batch losses and gradients sampled at each iteration to build a model of the loss function. Our model also makes use of any known lower bound of the loss function by using truncation, e.g. most losses are lower-bounded by zero. We then approximately minimize this model at each iteration to compute the next step. We show how MoMo can be used in combination with any momentum-based method, and showcase this by developing MoMo-Adam - which is Adam with our new model-based adaptive learning rate. Additionally, for losses with unknown lower bounds, we develop on-the-fly estimates of a lower bound, that are incorporated in our model. Through extensive numerical experiments, we demonstrate that MoMo and MoMo-Adam improve over SGD-M and Adam in terms of accuracy and robustness to hyperparameter tuning for training image classifiers on MNIST, CIFAR10, CIFAR100, Imagenet, recommender systems on the Criteo dataset, and a transformer model on the translation task IWSLT14.Comment: 25 pages, 11 figure

    Imaging of lung transplant complications

    Get PDF
    AbstractSince the late 1980s, lung transplantation has emerged as a valid treatment option for some patients with advanced non-neoplastic lung disease. Long-term survival of lung transplant recipients, however, is lower than that of patients with other types of transplantation, because of numerous specific postoperative complications. Thanks to X-ray and CT, radiologists can guide clinicians, helped in this diagnostic approach by the time between the date of injury and date of transplantation. We will detail in this pictorial review the immediate and late surgical complications, the immunological complications, the infectious complications and other late complications

    In Conversation with Mubin Shaikh: From Salafi Jihadist to Undercover Agent inside the "Toronto 18" Terrorist Group

    Get PDF
    This interview with former undercover agent Mubin Shaikh can help academics and security practitioners understand the key role played and the challenges faced by covert human intelligence sources within domestic terrorist groups. The interview highlights the identity crisis, the personal factors, and the allure of jihadi militancy that initially drove Shaikh to join a Salafi jihadist group. It investigates Shaikh’s process of disengagement from the Salafi jihadist belief system and his rediscovery of a moderate, inclusive, and benevolent form of Islam. It explores his work as an undercover agent for the Canadian Security Intelligence Service, the Royal Canadian Mounted Police, and the Integrated National Security Enforcement Team responsible for disrupting domestic terrorist groups. The “Toronto 18” terrorist cell, the key role played by undercover agents in preventing terrorist action, and the challenges posed by entrapment are also discussed

    Pancreatico-gastric fistula arising from IPMN associated with ductal adenocarcinoma of the pancreas: a case report and a literature review

    Get PDF
    IntroductionAn intraductal papillary mucinous neoplasm (IPMN) is a potentially malignant cystic tumor that is characterized by an excessive papillary proliferation of mucin-producing epithelial cells. The IPMN usually exhibits different degrees of dysplasia and is accompanied by cystic dilation of the main pancreatic duct (MPD) or side branch. We report a case of an IPMN that has penetrated the stomach and has differentiated into an adenocarcinoma.Case presentationA 69-year-old female, suffering from chronic pancreatitis of unknown etiology, visited our outpatient clinic with complaints of sudden weight loss, diarrhea, and abdominal pain. She underwent several examinations to evaluate the reasons for her sudden onset of symptoms. A gastroscopy showed an ulcerated lesion covered with mucus. CT and magnetic resonance cholangiopancreatography images revealed that the MPD was dilated to 1.3 cm with a fistula formation between the MPD and the stomach. After a multidisciplinary discussion of this case, a total pancreatectomy was proposed. An en bloc total pancreatectomy with gastric wedge resection including the fistula together with splenectomy was carried out. A Roux-en-Y choledochojejunostomy and gastrojejunostomy were performed. Histology results revealed the association of IPMN with invasive carcinoma.DiscussionMany reports on IPMN of the pancreas have been published recently. Fistula formation between IPMN and adjacent organs is possible. Given the CT and endoscopic ultrasonography findings, it shows that in our case a main duct IPMN (MD-IPMN) formed a pancreatico-gastric fistula. We point out that the adherence of invasive cancer cells contributed to the fistula formation between the pancreas and the stomach.ConclusionThis case report provides evidence for the possibility of IPMN becoming complicated with pancreatico-gastric fistula. Thus, we suggest that surgical resection should be considered in the case of MD-IPMN because of its high propensity for malignant transformation

    Microbial Extracellular Polymeric Substances: Ecological Function and Impact on Soil Aggregation

    Get PDF
    A wide range of microorganisms produce extracellular polymeric substances (EPS), highly hydrated polymers that are mainly composed of polysaccharides, proteins, and DNA. EPS are fundamental for microbial life and provide an ideal environment for chemical reactions, nutrient entrapment, and protection against environmental stresses such as salinity and drought. Microbial EPS can enhance the aggregation of soil particles and benefit plants by maintaining the moisture of the environment and trapping nutrients. In addition, EPS have unique characteristics, such as biocompatibility, gelling, and thickening capabilities, with industrial applications. However, despite decades of research on the industrial potential of EPS, only a few polymers are widely used in different areas, especially in agriculture. This review provides an overview of current knowledge on the ecological functions of microbial EPSs and their application in agricultural soils to improve soil particle aggregation, an important factor for soil structure, health, and fertility

    Responses of Acidobacteria Granulicella sp. WH15 to High Carbon Revealed by Integrated Omics Analyses

    Get PDF
    The phylum Acidobacteria is widely distributed in soils, but few representatives have been cultured. In general, Acidobacteria are oligotrophs and exhibit slow growth under laboratory conditions. We sequenced the genome of Granulicella sp. WH15, a strain obtained from decaying wood, and determined the bacterial transcriptome and proteome under growth in poor medium with a low or high concentration of sugar. We detected the presence of 217 carbohydrate-associated enzymes in the genome of strain WH15. Integrated analysis of the transcriptomic and proteomic profiles showed that high sugar triggered a stress response. As part of this response, transcripts related to cell wall stress, such as sigma factor σW and toxin–antitoxin (TA) systems, were upregulated, as were several proteins involved in detoxification and repair, including MdtA and OprM. KEGG metabolic pathway analysis indicated the repression of carbon metabolism (especially the pentose phosphate pathway) and the reduction of protein synthesis, carbohydrate metabolism, and cell division, suggesting the arrest of cell activity and growth. In summary, the stress response of Granulicella sp. WH15 induced by the presence of a high sugar concentration in the medium resulted in the intensification of secretion functions to eliminate toxic compounds and the reallocation of resources to cell maintenance instead of growth

    Development of targeted therapy for ovarian cancer mediated by a plasmid expressing diphtheria toxin under the control of H19 regulatory sequences

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Ovarian cancer ascites fluid (OCAF), contains malignant cells, is usually present in women with an advanced stage disease and currently has no effective therapy. Hence, we developed a new therapy strategy to target the expression of diphtheria toxin gene under the control of H19 regulatory sequences in ovarian tumor cells. H19 RNA is present at high levels in human cancer tissues (including ovarian cancer), while existing at a nearly undetectable level in the surrounding normal tissue.</p> <p>Methods</p> <p>H19 gene expression was tested in cells from OCAF by the in-situ hybridization technique (ISH) using an H19 RNA probe. The therapeutic potential of the toxin vector DTA-H19 was tested in ovarian carcinoma cell lines and in a heterotopic animal model for ovarian cancer.</p> <p>Results</p> <p>H19 RNA was detected in 90% of patients with OCAF as determined by ISH. Intratumoral injection of DTA-H19 into ectopically developed tumors caused 40% inhibition of tumor growth.</p> <p>Conclusion</p> <p>These observations may be the first step towards a major breakthrough in the treatment of human OCAF, while the effect in solid tumors required further investigation. It should enable us to identify likely non-responders in advance, and to treat patients who are resistant to all known therapies, thereby avoiding treatment failure.</p

    Numerical model validation for mooring systems: Method and application for wave energy converters

    Get PDF
    PublishedArticleMooring systems are key sub-systems of wave energy devices. The design of mooring systems is challenging because overdesign of the mooring system incurs a significant cost penalty, while underdesign may lead to a premature failure. Incorrect design could also reduce the power production. It is therefore important to develop mooring systems which are specific for wave energy applications. In particular, very compliant mooring systems which allow the system to be highly dynamic are being developed. The validation of numerical models with data from physical experiments would facilitate the development of appropriate mooring solutions. This paper presents tank test results for a scale model of the buoy and mooring used at the South West Mooring Test Facility (SWMTF), an offshore facility developed to conduct long-term sea trials for wave energy device moorings. The mooring system investigated is a compliant 3 leg catenary mooring system using Nylon ropes in the water column. Preliminary static, quasi-static, decay, regular and irregular wave tests were conducted on the 1:5 scale model, using the Ifremer basin in Brest. A corresponding numerical model was developed with a time-domain mooring modelling tool, inputting hydrodynamic data from a radiation/diffraction potential modelling program. After the calibration of several hydrodynamic parameters (added mass, damping and mean drift), the numerical model demonstrated good agreement with the experiment, providing an accurate prediction of the maximum mooring loads in irregular waves. However, results show large differences with the field test results, mainly because of the anchor position. The methods and procedures presented will allow the effective validation of numerical models to enable the development of appropriate mooring systems in wave energy applications.The authors acknowledge the support of the MERiFIC (4122) project partners (Marine Energy in Far Peripheral and Island Communities, http://www.merific.eu) and of MARINET, a European Community Research Infrastructure Action under the FP7 Capacities Specific Programme (262552) (www.fp7-marinet.eu). The authors would like to acknowledge the support of the South West Regional Development Agency for its support through the PRIMaRE institution and the support towards the FabTest through the Regional Growth Fund. The authors are grateful for the valuable support of the Ifremer team: Emmanuel Mansuy, Aurélien Tancray, Christophe Maisondieu and Peter Davies. The authors also want to thank Orcina for their technical support
    • 

    corecore